1. Field of the Invention
The present invention relates to a remover for injection-molded articles which is adapted to automatically remove the injection-molded article of a plastic material provided by an injection machine.
2. Description of the Prior Art
Generally, an injection-molded plastic article provided by the the injection machine is adapted to be automatically removed by an injection-molded article remover. The conventional automatic removing steps will be detailed with referring to FIGS. 5(a) to 5(j) and FIGS. 6 (a) to 6(h) as attached.
(a) A front mold 2 mounted to a stationary platen 1 and a movable half 4 carried by a movable platen 3 are in the state of being clamped. Plastic melt is injected into a cavity (not shown) defined by the front mold 2 and the movable half 4 so as to be molded into a predetermined shape. A grasping member 5A in a removing mechanism (not shown) waits in a predetermined waiting position. A mold-open signal is then given from a control means (not shown) to an open-close mechanism (not shown) for the movable half 4. PA0 (b) The movable half 4 starts the mold-open operation. PA0 (c) The movable half 4 reaches an extreme position in the mold-open operation. PA0 (d) The control means gives to the removing mechanism a signal causing the grasping member 5A to start entering the mold area. PA0 (e) The grasping member 5A enters the mold area based on numerical control by the control means. PA0 (f) The grasping member 5A reaches a predetermined position in the mold area based on numerical control by the control means. PA0 (g) The control means gives an actuation-start signal to an actuator (not shown) for an ejector. PA0 (h) The ejector (not shown) starts actuation. PA0 (i) The ejector forces out an injection-molded article 6 and the grasping member 5A attractes and holds (i.e., by chucking) the injection-molded article 6 through actuation of pneumatic equipment assembled in the removing mechanism. PA0 (j) The chucking of the molded article 6 by the grasping member 5A is recognized. PA0 (k) The control means gives to the removing mechanism a draw out-start signal for causing the grasping member 5A to start drawing out the molded article from the mold. PA0 (l) The grasping member 5A moves drawing out the molded article based on numerical control by the control means. PA0 (m) The draw-out movement of the grasping member 5A finishes. PA0 (n) The control means gives to the removing mechanism a withdrawal-start signal for causing the grasping member 5A to withdraw from the mold area. PA0 (o) The grasping member 5A moves to withdraw from the mold area based on numerical control by the control means. PA0 (p) The withdrawal movement of the grapsing member 5A finishes. PA0 (q) The control means gives to the open-close mechanism for the movable half 4 a mold-close signal, and in turn, a start signal for a next cycle. PA0 (r) The movable half 4 starts to more to the mold-close operation. PA0 (s) The movable half 4 is brought into the mold-close state, i.e, the state (a) wherein the movable half 4 and the front mold are being clamped. The above procedure will be repeated allowing the molded articles 6 to be removed from the mold continuously.
The above removing procedure is performed by means of a sequence control and thus has such problems that it takes a relatively long time to remove the molded articles and requires a longer cycle of the injection-molding operation.
The conventional removing procedure suffers the disadvantage of loss of time between the steps (q) and (r), such as last time for scanning in the computer program and lost time required for receiving and transmitting signals in the sequencer. There occurs loss of time also in actuation of the open-close mechanism for the movable half during the mold-close operation, and in pressure transmission in a feeding passage (hydraulic piping) for a working fluid. It has been ascertained that actual measurements of the loss of time total to 0.2 to 0.4 sec. The loss of time is absolutely unnecessary in the molding and removing operation.